***HELP Code 42 and Code 43 HELP***

[1987 Texas Jimmy]

I've been reading for hours on these two trouble codes I think I have a list of about 7 different parts that'll total more than $150!!! I have confused my self silly.

Last week check engine light comes on and throws out 42 and 43. So I check underneath the hood and all looks okay. So I reset the battery and drive it for a couple of more days.

Today, truck starts running like crap check engine light comes on for a while then off. Try to do the diagnostics and nothing! Won't even go into the flashing check engine light 12. Reset battery with no luck. What do I do????? Truck doesn't want to start unless I have foot on gas, stays in gear way way way to long and under any load it just bogs down.

I gotta get this fixed because it is my transportation. Don't have much money hince a 18 year old vehicle. Don't get me wrong I love her, but she's really makin' my life miserable.

You guys are the gurus, not me so any help would be great. Thanks in advance...

 

[gonger]

i had similar codes, caused from plug wire shorting on exhaust, changed out cap/rotor/wires, took spark module back. set timing.

 

[Thunder]

Do a tune up. Change the distributor module (40 bucks). May also be the magnetic pick up coil. have to pull the dist to change that.

 

[eagle mark]

I think last week when you got a code 42 and 43
42. Fault at electronic spark timing circuit (sets when timing is set also, clear code and verify that it does not return.)
43. Low voltage at electronic spark timing circuit

It was trying to tell you it was going bad. EST is the module in your distributor you can get out without pulling the distributor. Just about any parts store will check it for you. Check it three times, if it fails any of them replace it. That module is known for having an intermitent problem when going bad. You also sound like you may have been is limp home mode last it was running.

 

[dyeager535]

Sounds like you figured out the problem in the other thread?

The knock sensor connector is almost universal for the early GM stuff, so if you need it, hit up the wrecking yards and find a good one. I hate buying new connectors unless they are impossible to find in the yards, they seem to cost more than a new sensor in many cases!

The sensor itself is somewhat tuned to the engine (305 and 350 ones are different for example) so when getting one, just make sure you've got the right application. You could always run used here too, but they CAN fail. (not like that is any worse than now lol)

I'd fix your connector/sensor issue and see what happens. More than likely all the codes disappear!

 

[1987 Texas Jimmy]

Sounds good. I leave tonight for a few days so I wont be able to work on it till Sunday. I'll keep y'all posted on any updates. Thanks

 

[1987 Texas Jimmy]

One more symptom to add to the list for diagnostics. When I start the truck it dies unless I have the gas pedal pushed in a little bit. After it warms it has a hesitating idle!

 

[dyeager535]

Fix known problems first, see what problems still exist afterwards, if any, then back to troubleshooting.